Glossary of Terms .....................................................................................................................................................7
AFL Drawing Symbol Keys......................................................................................................................................8
1.1 Electric Shock Hazard.................................................................................................................................9
1.3 Chemical Hazard........................................................................................................................................10
3.1 Parts Lists ...................................................................................................................................................12
3.1.1 Equipment 60-056100 Parts List .............................................................................................................................. 12
3.1.2Unit 1 Fibre Fed Tunnel Amplifier 60-056101 Parts List ......................................................................................... 12
3.1.3Unit 2 Fibre Fed Tunnel Amplifier 60-056102 Parts List ......................................................................................... 13
5.2.7450MHz 20W Power Amplifier (12-004201)............................................................................................................42
6.1 Initial Installation Record .........................................................................................................................56
7.1 General Procedures....................................................................................................................................58
7.1.5Checking service .......................................................................................................................................................60
7.1.6Service Support .........................................................................................................................................................60
7.2 Tools & Test Equipment............................................................................................................................60
7.3 Care of Modules .........................................................................................................................................61
7.3.5Low Power Amplifier Replacement ..........................................................................................................................62
This handbook is for use solely with the equipment identified by the AFL Part Number
shown on the front cover. It is not to be used with any other equipment unless specifically
authorised by Aerial Facilities Limited. This is a controlled release document and, as such,
becomes a part of Aerial Facilities’ Total Quality Management System. Alterations and
modification may therefore only be performed by Aerial Facilities Ltd.
Purpose
The purpose of this handbook is to provide the user/maintainer with sufficient information
to service and repair the equipment to the level agreed. Maintenance and adjustments to any
deeper level must be performed by AFL, normally at the company’s repair facility in
Chesham, England.
This handbook has been prepared in accordance with BS 4884, and AFL’s Quality
procedures, which maintain the company’s registration to ISO 9001: 1994 and to the
R&TTE Directive of the European Parliament. Copies of the relevant certificates and the
company Quality Manual can be supplied on application to the Quality Manager.
This document fulfils the relevant requirements of Article 6 of the R&TTE Directive.
Limitation of Information Notice
This manual is written for the use of technically competent operators/service persons. No
liability is accepted by AFL for use or misuse of this manual, the information contained
therein, or the consequences of any actions resulting from the use of the said information,
including, but not limited to, descriptive, procedural, typographical, arithmetical, or listing
errors.
Furthermore, AFL does not warrant the absolute accuracy of the information contained
within this manual, or it’s completeness, fitness for purpose, or scope.
AFL has a policy of continuous product development and enhancement, and as such,
reserves the right to amend, alter, update and generally change the contents, appearance and
pertinence of this document without notice.
All AFL products carry a twelve month warranty from date of shipment. The warranty is
expressly on a return to base repair or exchange basis and the warranty cover does not
extend to on-site repair or complete unit exchange.
H/book Number:-60-056100HBKMFCC
Issue No:-2
P B L Tunnel Units 1 & 2
Maintenance Handbook
Date:-04/01/2006
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6 of 63
Glossary
of Terms
Repeater or
Cell Enhancer A Radio Frequency (RF) amplifier which can simultaneously
amplify and re-broadcast Mobile Station (MS) and Base
Transceiver Station (BTS) signals.
Band SelectiveRepeater A Cell Enhancer designed for operation on a range of channels
within a specified frequency band.
Channel Selective
Repeater A Cell Enhancer, designed for operation on specified channel(s)
within a specified frequency band. Channel frequencies may be
factory set or on-site programmable.
BTS Base Transceiver Station
C/NR Carrier-to-Noise Ratio
Downlink (D.L.) RF signals transmitted from the BTS and to the MS
Uplink (U.L.) RF signals transmitted from the MS to the BTS
EMC Electromagnetic Compatibility
GND Ground
DC Direct Current
AC Alternating Current
ID Identification Number
OIP3 Output Third Order Intercept Point = RF
+(C/I)/2
out
LED Light Emitting Diode
M.S. Mobile Station
N/A Not Applicable
N/C No Connection
NF Noise Figure
RF Radio Frequency
Rx Receiver
Tx Transmitter
S/N Serial Number
H/book Number:-60-056100HBKMFCC
Issue No:-2
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Drawing Symbol Keys
AFL
H/book Number:-60-056100HBKMFCC
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Date:-04/01/2006
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1. SAFETY CONSIDERATIONS
1.1 Electric Shock Hazard
Electrical shocks due to faulty mains driven power supplies.
Whilst ever potentially present in any electrical equipment, such a condition would be
minimised by quality installation practice and thorough testing at:
a) Original assembly.
b) Commissioning.
c) Regular intervals, thereafter.
All test equipment to be in good working order prior to its use. High current power supplies
can be dangerous because of the possibility of substantial arcing. Always switch off during
disconnection and reconnection.
1.2 RF Radiation Hazard
“CAUTION: This equipment is approved for antennas mounted on fixed outdoor
permanent structures. A minimum separation distance of 2 metres must be maintained
between the radiating elements and any nearby persons. A maximum antenna gain of 21
dBi may be used. Operating this equipment without regard to these restrictions will result
in RF exposure levels above the limits allowed by FCC rules.”
This equipment complies with part 90 of the FCC rules. Any changes or modifications not
expressly approved by the manufacturer could void the user’s authority to operate the
equipment.
RF radiation, (especially at UHF frequencies) arising from transmitter outputs connected to
AFL’s equipment, must be considered a safety hazard.
This condition might only occur in the event of cable disconnection, or because a ‘spare’
output has been left unterminated. Either of these conditions would impair the system’s
efficiency. No investigation should be carried out until all
RF power sources have been
removed. This would always be a wise precaution, despite the severe mismatch between the
impedance of an N type connector at 50, and that of free space at 377, which would
severely mitigate against the efficient radiation of RF power. Radio frequency burns could
also be a hazard, if any RF power carrying components were to be carelessly touched!
Antenna positions should be chosen to comply with requirements (both local & statutory)
regarding exposure of personnel to RF radiation. When connected to an antenna, the unit is
capable of producing RF field strengths, which may exceed guideline safe values especially if
used with antennas having appreciable gain. In this regard the use of directional antennas
with backscreens and a strict site rule that personnel must remain behind the screen while the
RF power is on, is strongly recommended.
Where the equipment is used near power lines, or in association with temporary masts not
having lightning protection, the use of a safety earth connected to the case-earthing bolt is
strongly advised.
H/book Number:-60-056100HBKMFCC
Issue No:-2
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Maintenance Handbook
Date:-04/01/2006
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9 of 63
Chemical Hazard
1.3
Beryllium Oxide, also known as Beryllium Monoxide, or Thermalox™, is sometimes used
in devices within equipment produced by Aerial Facilities Ltd. Beryllium oxide dust can be
toxic if inhaled, leading to chronic respiratory problems. It is harmless if ingested or by
contact.
Products that contain beryllium are load terminations (dummy loads) and some power
amplifiers. These products can be identified by a yellow and black “skull and crossbones”
danger symbol (shown above). They are marked as hazardous in line with international
regulations, but pose no threat under normal circumstances. Only if a component containing
beryllium oxide has suffered catastrophic failure, or exploded, will there be any danger of the
formation of dust. Any dust that has been created will be contained within the equipment
module as long as the module remains sealed. For this reason, any module carrying the
yellow and black danger sign should not be opened. If the equipment is suspected of failure,
or is at the end of its life-cycle, it must be returned to Aerial Facilities Ltd for disposal.
To return such equipment, please contact the Quality Department, who will give you a
Returned Materials Authorisation (RMA) number. Please quote this number on the packing
documents, and on all correspondence relating to the shipment.
PolyTetraFluoroEthylene, (P.T.F.E.) and P.T.F.E. Composite Materials
Many modules/components in AFL equipment contain P.T.F.E. as part of the RF insulation
barrier.
This material should never be heated to the point where smoke or fumes are evolved. Any
person feeling drowsy after coming into contact with P.T.F.E. especially dust or fumes
should seek medical attention.
Emergency Contact Numbers
1.4
The AFL Quality Department can be contacted on:
Telephone +44 (0)1494 777000
Fax +44 (0)1494 777002
e-mail qa@aerial.co.uk
H/book Number:-60-056100HBKMFCC
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2. OVERVIEW/SYSTEM DESCRIPTION
The AFL Fibre feed Amplifier for the Pasadena Blue line project is a 2 way on-band RF
amplifier. The primary application is as an interface between the fibre optical link from UNIT
ONE (Port 3 Downlink/Port 4 Uplink) and the tunnel antenna/leaky feeder system(Ports J3
and J4). There are two units, one designated ‘UNIT 1’, which is a fibre Tx or Rx with an
associated bandpass filter for each RF path, and ‘UNIT 2’ (a Bi-Directional amplifier) for the
frequencies in the 483-486MHz range.
Each unit is housed in an environmentally protected IP65 steel wall-mount case. Handles are
provided for carrying the unit and the door is fitted with locks. The unit interfaces with ‘N’
type female connectors for RF connections and heavy duty connectors for routing of AC
power supply input and alarm output wiring. Cable glands are provided for routing of the
Fibre optic cable in to the units.
The downlink signal path is as follows: The signal is received by a fibre optic receiver
located in unit 1 it is then split in to two paths using bandpass filtering for the frequencies
required. One downlink path is contained in unit 1 the other in unit 2. To provide the
required gain to reach the required signal levels, low-noise amplifiers (LNA’s) are used in
each path, these being followed by power amplifier modules to provide the required
intermodulation performance. The paths are then recombined using bandpass filtering (in unit
2) and are fed to the radiating cable. Gain adjustment is available locally using switched
attenuators.
Similarly the uplink path is taken from the radiating cable and spilt into the two required
frequency bands. One uplink path is contained in unit 1 the other in unit 2, again to provide
the required gain to reach the required signal levels, low-noise amplifiers (LNA’s) are used in
each path, these being followed by power amplifier modules to provide the required
intermodulation performance. The paths are then recombined using bandpass filtering and are
fed to a fibre optic transmitter. Gain adjustment is available locally using switched
attenuators.
To provide adequate selectivity in the Downlink and Uplink paths, combline design
duplexers are used at the input and output ports.
Note that “Downlink” refers to the RF path from FO receiver to the leaky feeder port and that
“Uplink” refers to the RF path from the leaky feeder port to either the FO transmitter or offair antenna.
Better than –13dBm uplink
(measure with 30KHz BW with max gain setting)
Out-band Spurious up to 3GHz: Better than –90dBc
Uplink Channels:
486.0625MHz
486.2875MHz
486.3125MHz
486.5625MHz
H/book Number:-60-056100HBKMFCC
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e
Mechanical Specifications
3.3
3.3.1 Unit 1 60-056101 Mechanical Specification
PARAMETER SPECIFICATION
Size:
height:
width:
depth:
620 mm
420 mm
260 mm
(excluding connectors, heatsinks, handles and feet)
Fixings:
Weight:
Temperature
Range:
operational:
storage:
Humidity:
Environmental Protection:
Case:
Finish:
Heatsinks:
Handles:
Supply Cable:
4 holes on 250 mm (h) x 470 mm (w)
50 kg (approx.)
-20°C to +50°C
-40°C to +70°C
10% to 95% non-condensing
IP65 (with door closed and all ports terminated)
RAL 7032
Black anodised
Black (where fitted)
Unit supplied with 3-pin IP68 connector for
customer interface with AC input.
3.3.2 Unit 2 60-056102 Mechanical Specification
Size:
height:
width:
depth:
620 mm
420 mm
250 mm
(excluding connectors, heatsinks, handles and f
Temperature Range:
Environmental Protection:
Finish:
Fixings:
Weight:
operational:
storage:
Humidity:
Case:
Heatsinks:
Handles:
4 holes on 500 mm (h) x 467 mm (w)
50 kg (approx.)
-20°C to +50°C
-40°C to +70°C
10% to 95% non-condensing
IP65 (with door closed and all ports terminated)
RAL 7032
Black anodised
Black (where fitted)
Supply Cable: Unit supplied with 3-pin IP68 connector for
customer interface with AC input.
H/book Number:-60-056100HBKMFCC
Issue No:-2
P B L Tunnel Units 1 & 2
Maintenance Handbook
Date:-04/01/2006
Page:-
17 of 63
4. SYSTEM DRAWINGS
Drg. N. 60-056190, Location 2 UHF 1 Case Outline Drawing
4.1
A
B
C
D
E
BYDAT EDESCRI PT IO NNo
DBS
DBSDECIMAL EQUIV'S
DBSECN27472A
15/10/02
21/10/02
30/10/02
F
3
A
485/486MHz INP UT
470/473MHz INPUT/OUTPUT
ISSUE
60-056190
PR ODUC TION IS S UE
1A
1B
PASADENA BLUE LI NE. LOCAT ION 2.
483MHz OUTPUT
BDA 470/ 473MHz. OUTLINE DRAWING
TITLE
CUSTO MER DRAWING.No
500 [1'-7.7"]
LOCKABLE
DOOR
CATCH
ALARMS
High
volt age
DANGER
Pr oduct ref :
Aerial Facilities
Li m i t ed
CE- / - N
460 [1'-6.1"]
420 [1'-4.5"]
BPA 470/473MHz
Heavy
CAUTION
PSU ALARM
467 [1'-6.4"]
M6 EA RTH STUD
England
Fax : 01494 777000
Aerial Facilities Limit ed
Fax : 01494 777002
709 [2'-3.9"]
260 [10.3"]
1 2345678 9
A
620 [2'-0.4"]
B
H/book Number:-60-056100HBKMFCC
C
Issue No:-2
CAB LE GLA NDS (FIBRE OPTICS)
MATERIAL: MILD STEEL
FINISH: PAINTED TO RAL 9017
WALL FIXINGS: M8 (5/16")
RF CONNECTORS: N TYP E FEM ALE
ENVIRONMENTAL CLASS.: IP65
SE MI -GLOSS TRAFFIC B LA CK
D
E
P B L Tunnel Units 1 & 2
Maintenance Handbook
Date:-04/01/2006
115V AC INPUT
Page:-
THIS IS A PROPRIETARY DESIGN OF AERIAL F ACILITIES LTD.
REPRODUCTION OR USE OF THIS DESIGN BY OTHERS IS
PERMISSIBLE O NLY IF EXPRESSL Y AUTHORISED IN WRIT ING
BY AERIAL FACIL ITIES LT D.
15/10/02
APPD
DAT E
DBS
CHKD
DRAWN
18 of 63
1:8
SCALE
NO DECIMAL PL ACE ± 1 mm
ONE DECIM AL PL ACE ± 0 .3 mm
TWO DECIMAL PLACES ± 0.1mm
TO L ERA NCES
1 2345678 9
ALL DIMENSIONS ARE IN mm
UNLESS OT HERWISE STATED
PBGD
F
Drg. N. 60-056192, Location 2 UHF 2 Case Outline Drawing
4.2
A
B
C
D
89
MATERIAL: MILD STE EL
FINISH: PAINTED TO RAL 9017
WALL FIXINGS: M8 (5/16")
RF CONNECTORS: N TYPE FEMALE
ENVIRONMENTAL CLASS.: IP65
SEMI-GLOSS TRAFFIC BLACK
7
E
BYDAT EDESCRIP TIO NNo
DBS
DBSDECIMA L EQUIV 'S
DBSECN274 72A
15/10/02
21/10/02
30/10/02
ISSUE
F
3
A
60-056191
PRODUCTION ISSUE
1A
1B
PASADENA BLUE LINE. LOCATI ON 2.
BDA 483/485MHz. OUTLINE DRAWING
TITLE
CUSTO MER DRAWING.No
6
500 [1'-7.7"]
5
Product ref :
Aerial Facilities
Lim i ted
497 [1'-7.6"]
420 [1'-4.5"]
4
CE- / - N
BP A 483/ 485MHz
Heavy
CAUTION
LOCKABLE
DOOR
CATCH
ALARMS
High
voltage
DANGER
467 [1'-6.4"]
PSU ALARM
M6 EARTH STUD
England
Fax : 01494 777000
Aerial Facilit ies Limited
Fax : 01494 777002
1:8
709 [2'-3.9"]
115V A C INPUT
3
470/473MHz
485/486MHz OUTPUT
INPUT
LCX
800MHz
250 [9.9"]
12
483MHz INPUT
A
620 [2'-0.4"]
B
H/book Number:-60-056100HBKMFCC
C
Issue No:-2
VHF
D
E
P B L Tunnel Units 1 & 2
Maintenance Handbook
Date:-04/01/2006
Page:-
THIS IS A PROPRIETARY DESIGN OF AERIAL FACILITIES LT D.
REPRO DUCTIO N O R USE O F T HIS DES IGN B Y OT HERS IS
PERMISSIBLE ONLY IF EXPRESSL Y AUTHORISED IN WRITING
BY AERIAL FACILITIES LTD.
15/10/02
APPD
DATE
DBS
CHKD
DRAWN
F
19 of 63
TO L ERANCE SSCAL E
NO DECIMA L P LA CE ± 1 mm
ONE DECIMAL PLACE ± 0.3mm
TWO DECIMAL PL ACES ± 0.1m m
123456789
PBGD
AL L DIMENS IONS ARE IN m m
UNLESS OT HERWISE STATED
Complete Pasadena Metro System Diagram
4.3
Remote Locations
UNIT 1
-15dBm
3
3
4
E
-15dBm
-15dBm
E
-15dBm
60-056101
UNIT 2
60-056102
T5
O
O
T6
02-007302
470MHz
02-007302
483MHz
02-007302
473MHz
02-007302
485-486MHz
E
-17dBm
HI
AGC
DET
20dB 30dB
AGC
16dB20dB20dB
DET
FG
20dB 30dB
16dB20dB20dB
12-00180111-007302
dB
AGC
12-00420111-007302
dB
AGC
30dBm
dB
28dBm
02-010401
11-00730211-006102 11-007302
dB
11-00730211-006102 11-007302
02-013401
470MHz
02-013401
02-013401
483MHz
02-010401
02-013401
485-486MHz
473MHz
02-007302
02-007302
J
470-475MHz
483-486MHz
-57dBm
27dBm
-57dBm
H
L
20dBm
18dBm
-50dBm
-50dBm
LCX
LCX
20dBm
18dBm
-50dBm
-50dBm
VHF
U
J3
J4
H/book Number:-60-056100HBKMFCC
Issue No:-2
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Maintenance Handbook
Date:-04/01/2006
Page:-
20 of 63
5. SUB-UNIT MODULES
5.1 Unit 1 (60-056101)
5.1.1 Bandpass Filters (02-007302)
5.1.1.1 Description
The bandpass filters are multi-section designs with a bandwidth dependent upon the
passband frequencies, (both tuned to customer requirements). The response shape is
basically Chebyshev with a passband design ripple of 0.1dB. The filters are of combline
design, and are carefully aligned during manufacture in order to optimise the insertion
loss, VSWR and intermodulation characteristics of the unit. The tuned elements are
silver-plated to reduce surface ohmic losses and maintain a good VSWR figure and 50
load at the input and output ports.
No adjustments should be attempted without full network sweep analysis facilities to
monitor both insertion loss and VSWR simultaneously.
The FO units consist of a receiver & transmitter, which modulates the RF signal onto a laser
carrier and transmits it via fibre/optic cable to a receiver unit some distance away where it is
demodulated back to the original RF signal with very small values of accrued attenuation.
Both transmitter and receiver modules have their own dedicated alarm outputs (volt-free
relay contacts) which are integrated/summed into the main alarm system. The alarms are
non-latching, so an alarm condition may revert to ‘good’ if the fault clears for any reason
(e.g. momentary DC power loss).
The AFL Fibre Optic transmitters and receivers both have two LED status indicators, one
on each module showing DC power and the other indicating ‘Laser On’ for the transmitter,
and ‘Carrier Being Received’ for the receiver.
Typically the input to transmitter units will be at a level of between –30 and –15 dBm. The
RF gain of a pair (Tx to Rx) units is factory set to give a 0dB gain, but this is with a short,
low loss fibre. In determining the performance of any link, the insertion loss of the fibre and
any power splitters fitted must be considered. A general rule of thumb figure would be
around 0.5 - 1.5dB loss per fibre Kilometre.
The fibre optic transmitter module (20-004001) takes two RF inputs, one containing signals
between 20- and 35 MHz (generally used by laser-modems for carrying alarm, and status
information between sites) and another containing signals between 70 MHz and 2.5 GHz
(the main RF carrier) and modulates them both onto to a fibre optic cable. The Laser Tx
module uses a Class IIIa Transmitting Laser Device, see laser safety precautions in section
1. The receiver module (20-004101) takes a fibre optic signal, and converts this into two RF
outputs, one containing signals between 20- and 35 MHz and another containing signals
between 70 MHz and 2.5 GHz.
5.1.2.2 Fibre Optic Units Technical Specification
PARAMETERSPECIFICATION
Frequency range (Traffic)70-2500MHz
Frequency range (‘Data’)20-35 MHz
Tx Max. Optical Output Power
+10dBm
1.5
Rx Alarm:@10dBm Fibre Loss
Gain (back-to-back connection)+10dB
Flatness 70-2500MHz +/-1.5dB
IP3 (All conditions)>+30dB
Noise Figure (back-back connector): <40dB
Power Supply: 12V DC –Ve GND
Consumption:
350mA (typical) @ 12V DC (Rx)
100mA
typical) @ 12V DC (Tx)
P B L Tunnel Units 1 & 2
Maintenance Handbook
H/book Number:-60-056100HBKMFCC
Issue No:-2
Date:-04/01/2006
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22 of 63
5.1.2.3 ‘D’ Connector Pinouts
Rx ‘D’ Type Female Connector
Pin N. Signal Description
1 +12V DC Power
2 No Connection
3 Power Ground
4 No Connection
5 No Connection
6 O/C. Alarm
7 Relay Alarm Contact (N.C)
8 Relay Alarm Contact (Common)
9 Relay Alarm Contact (N.O)
Tx ‘D’ Type Female Connector
Pin N. Signal Description
1 +12V DC Power
2 No Connection
3 Power Ground
4 No Connection
5 No Connection
6 O/C Alarm
7 Relay Alarm Contact (N.C)
8 Relay Alarm Contact (Common)
9 Relay Alarm Contact (N.O)
H/book Number:-60-056100HBKMFCC
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Maintenance Handbook
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23 of 63
5.1.3 JWS75-15/A PSU (96-300045)
5.1.3.1 Description
The power supply unit is a switched-mode type capable of supplying 24V DC at 3.25Amps
continuously. This PSU is used to provide power for the fibre optic modules which will
typically require less than 1.50 Amps at 15V DC, so the PSU will be used conservatively
ensuring a long operational lifetime.
No routine maintenance of the PSU is required. If a fault is suspected, then the output
voltage from the power supply may be measured on its output terminals. The output voltage
is set at test but can be adjusted by a multi-turn potentiometer mounted close to the DC
output terminals.
All the PSU’s used in AFL Cell Enhancers are capable of operation from either 110 or
220V nominal AC supplies. The line voltage is sensed automatically, so no adjustment or
link setting is needed by the operator.
5.1.3.2 Technical Specification
AC Input Supply:
110 or 220V nominal
Voltage:
90 to 132 or 180 to 264V
(absolute limits)
Frequency: 47 to 63Hz
DC Output Supply:
Voltage:
24V DC (nominal)
22 to 26V (absolute limits)
Current: 6.25A
H/book Number:-60-056100HBKMFCC
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Unit 2 (60-056102)
5.2
5.2.1 Bandpass Filter (02-013401)
5.2.1.1 Description
The bandpass filters are multi-section designs with a bandwidth dependent upon the
passband frequencies, (both tuned to customer requirements). The response shape is
basically Chebyshev with a passband design ripple of 0.1dB. The filters are of combline
design, and are carefully aligned during manufacture in order to optimise the insertion loss,
VSWR and intermodulation characteristics of the unit. The tuned elements are silver-plated
to reduce surface ohmic losses and maintain a good VSWR figure and 50 load at the input
and output ports. Being passive devices, the bandpass filters should have an extremely long
operational life and require no maintenance. Should a filter be suspect, it is usually most
time efficient to replace the module rather than attempt repair or re-tuning.
No adjustments should be attempted without full network sweep analysis facilities to
monitor both insertion loss and VSWR simultaneously.
FILTER 1 2.8 dB typical
FILTER 2 2.8 dB typical
FILTER 1 470-470.5MHz > 60 dB
FILTER 2 473-473.5MHz > 60 dB
Power Rating 250 Watt
Impedance 50 ohm
VSWR Better than 1.2:1
Connectors SMA female
H/book Number:-60-056100HBKMFCC
Issue No:-2
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Maintenance Handbook
Date:-04/01/2006
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25 of 63
5.2.2 Two Section Notch Filter (02-010401)
5.2.2.1 Description
Fitted in Unit 2 after the amplification stages is a 2 element notch filter (one in downlink,
one in uplink), which is designed to reject the uplink frequencies in the downlink path
and vice-versa. The notch filter is not required for Unit One as the rejection from the two
series bandpass filters as apposed to one, is sufficient to meet the specification.
5.2.2.2 Technical Specification (Uplink)
PARAMETER SPECIFICATION
Frequency range: 485.2-485.6 MHz
Stopband: 482.2 – 483.6MHz
N. of sections: 2
Attenuation: >40dB @ 482.2MHz
Insertion loss: 0.5dB
VSWR: Better than 1.2:1
Connectors: SMA
Power Handling: 50W maximum
Temperature
range:
operate: -10°C to +55°C
store: -30°C to +70°C
Weight: <3 kg
Size: 384 x 82.5 x 56.4mm
5.2.2.3 Technical Specification (Downlink)
Frequency range: 482.2-483.6 MHz
Stopband: 485.2-486.6MHz
N. of sections: 2
Attenuation: >40dB @ 485.2MHz
Insertion loss: 0.5dB
VSWR: Better than 1.2:1
Connectors: SMA
Power Handling: 50W maximum
operate: -10°C to +55°C Temperature
range:
store: -30°C to +70°C
Weight: <3 kg
Size: 384 x 82.5 x 56.4mm
H/book Number:-60-056100HBKMFCC
Issue No:-2
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Maintenance Handbook
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5.2.3 Crossband Couplers (07-004801 & 07-005705)
5.2.3.1 Description
The purpose of a crossband coupler is to either combine/split transmission signals from
different parts of the frequency spectrum.
The crossband coupler fitted here, is the means by which the separate UHF & GSM
frequency band signals are mixed to form a composite RF signal.
It basically comprises of a 3 port device, two filters, one a low pass the other a high pass, that
are then mixed and fed to a common output. The couplers are built into a machined
aluminium casing having a centre screening wall between the filter sections and lid secured
by screws at frequent intervals over its perimeter to obtain a tight seal and to ensure linearity
and stability of response.
5.2.3.2 Technical Specification (07-004801)
PARAMETER SPECIFICATION
Passband:
390-490MHz
700-900MHz
N. Of i/p ports: 2
N. Of o/p ports: 1
Insertion loss: 0.5dB (typical)
Isolation:
>40dB 390-490MHz
>40dB 700-900MHz
Impedance: 50Ω
Connectors: SMA female
Power rating: 50Watts (CW)
5.2.3.3 Technical Specification
PARAMETER SPECIFICATION
Passband:
250 MHz
380 MHz
70.0-250MHz
380-960MHz
Power Rating 50 Watts (CW)
Number of Input ports 2
Number of Output ports 1
Insertion loss 0.5 dB
Isolation > 50 dB 70-250 MHz
> 50 dB 380-960 MHz
(15 dB typical return loss 500-960)
In many practical applications for Cell Enhancers etc., the gain in each path is found to be
excessive. Therefore, provision is made within the unit for the setting of attenuation in
each path, to reduce the gain.
5.2.4.2 Switched Attenuators
The AFL switched attenuators are available in two different types; 0 – 30dB in 2 dB steps
(as in this case), or 0 – 15dB in 1 dB steps. The attenuation is simply set using the four
miniature toggle switches on the top of each unit. Each switch is clearly marked with the
attenuation it provides, and the total attenuation in line is the sum of the values switched
in. They are designed to maintain an accurate 50 impedance over their operating
frequency at both input and output.
The low noise amplifiers used are double or triple stage solid-state low-noise amplifiers.
Class A circuitry is used in the units to ensure excellent linearity over a very wide
dynamic range. The active devices are very moderately rated to provide a long troublefree working life. There are no adjustments on these amplifiers, and in the unlikely event
of failure then the entire amplifier should be replaced. Note that all LNA’s use similar DC
power circuit boards.
5.2.5.2 Technical Specification (11-006102)
PARAMETER SPECIFICATION
Frequency range: 70 – 500MHz
Bandwidth: <430MHz
Gain: 15.5dB (typical)
1dB Compression Point: +31dBm (typical)
3rd order intercept: +46dBm (typical)
Input return loss: >20dB
Output return loss: >20dB
VSWR: Better than 1.5:1
Noise figure: <4.8dB
Connectors: SMA female
Supply: 530mA @ 10 to 24V DC (typical)
Temperature range:
operational: -10°C to +60°C
storage: -40°C to +70°C
Weight: 260gms
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5.2.5.3 Drg. N. 11-006102, Low Noise Amplifier General Assembly
5.2.5.10 Drg. N. 11-007371, LNA DC Wiring Diagram
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5.2.6 3 Stage Amplifier Alarm Boards (12-002201)
5.2.6.1 Description
Amplifier Alarm Boards are fitted to monitor the bias conditions of AFL Class A amplifiers
which remain constant in normal operation. Any departure from normal bias conditions is a
result of device failure, excess temperature, over-driving or oscillation (excessive power).
In normal operation, the Class A bias circuit of the amplifier develops a constant voltage of
1.20V across the collector current setting resistor. The Amplifier Alarm Board is a window
comparator device, which is adjusted to sense a departure from this condition. Several
different alarm outputs are provided to simplify interfacing, (Relay Contact, Open Collector,
and TTL Logic Levels)
The basic version of the Alarm Board (12-002801) monitors a single amplifier stage. A
three-stage version (12-002201) is used on complex amplifiers where three separate
comparators have their outputs logically combined to a common output stage. Failure of any
one stage will activate the alarms.
Note that the alarm board has a green Light Emitting Diode located near to the centre of the
printed circuit board, which is illuminated on ‘Good’, and extinguished on ‘Alarm’. It is
therefore a simple matter to identify an active module failure, by searching for an Alarm
Board which has its green LED extinguished. A simple test of the alarm board is possible by
shorting across the monitor inputs, pins 1 and 2, 3 and 4 or across pins 5 and 6. This last
monitor input is inactive if the board has been converted to a two way alarm board. (Refer to
relevant amplifier alarm wiring diagram.)
1) Volt-free change over relay contacts.
2) Open collector NPN transistor pulls low on alarm.
3) TTL driver.
The use of precision voltage sources and resistors has eliminated the need for initial
adjustment or calibration, and the board will function correctly with a wide variation in
power supply voltage (8 to 30 volts, nominal supply is 12 or 24Volts).
There are two selectable link options on the three-way board:
LINK1 - Removed to convert to two-way alarm board.
LINK2 - Removed to isolate 0V from chassis earth.
The one way alarm board only has the 0V isolation link (LINK2) fitted.
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5.2.6.2 Technical Specification
PARAMETER SPECIFICATION
Operating voltage: 8 to 30V (floating earth)
Alarm Threshold: Vcc - 1.20 volt +15%
The power amplifiers fitted to this unit are multi-stage, solid state power amplifiers. Class
A circuitry is employed throughout the units to ensure excellent linearity over a wide
dynamic frequency range. All the semi-conductor devices are very conservatively rated to
ensure low device junction temperatures and a long, trouble free working lifetime.
The power amplifiers should require no maintenance over their operating lives. Under no
circumstances should the cover be removed or the side adjustments disturbed unless it is
certain that an amplifier has failed; since they are critically aligned during manufacture
and any re-alignment will require extensive test equipment.
5.2.7.2 Technical Specification
PARAMETER SPECIFICATION
Frequency Range: 350 – 550MHz (tuned to spec.)
Bandwidth: 20MHz (tuned to spec.)
Maximum Output Power: >20W (each)
Gain: 30dB
1dB Compression Point: <+43dBm
3rd Order Intercept Point: <+54dBm
VSWR: better than 1.45:1
Connectors: SMA female
Supply: 3.50A @ 24V DC
Size: 276 x 78 x 40mm (ex. Cons. & h’sink)
Weight: 1.5 kg (approx., excl. h’sink)
operational: -10°C to +55°C Temperature
range:
storage: -40°C to +70°C
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5.2.7.3 Drg. N. 12-004201, PA General Assembly
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5.2.7.4 Drg. N. 12-004270, PA Circuit Diagram
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5.2.7.5 Drg. N. 12-004270C1, PA Parts List(1)
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5.2.7.6 Drg. N. 12-004270C2, PA Parts List(2)
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5.2.7.7. Drg. N. 12-003670, PA to Alarm Wiring Details
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5.2.8 DC/DC Converter, 24V in, 12V 8A out (13-003011)
5.2.8.1 Description
The DC/DC converter fitted is an AFL assembled, high power PCB unit with an 8 amp @
24V in, 12V output capability. The circuit is basically an O.E.M semiconductor regulator
(one side of which has a heatsink mounting plate, that is usually bolted to the casing of a
Cell Enhancer) and smoothing components built onto a printed circuit board with screw
block terminations.
Note: no circuit diagram of the O.E.M. regulator is available. This unit should not be
repaired, only replaced.
5.2.8.2 Technical Specification
PARAMETER SPECIFICATION
Input Voltage Range: 18-28V DC
Output Voltage: 12V±0.5V
Max. Current Load: 8.0Amps
operation: -10°C to +55°C Temperature
Range:
storage: -40°C to +70°C
Size(PCB): 190 x 63mm
Weight (Loaded PCB): 291gms
5.2.8.3 Photo of Regulator PCB (regulator heatsink side)
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5.2.9 Wide Dynamic Range AGC (17-001105, Det. & 17-001201, Atten.)
5.2.9.1 Description
The equipment is fitted with a wide dynamic range Automatic Gain Control (AGC) system.
This is generally fitted in the Uplink path (not usually needed in the downlink path, as the
signal here is at an almost constant level), to avoid overloading the amplifiers (with the
associated performance degradation) should a mobile be operated very close to the unit.
The AFL wide dynamic range Automatic Gain Control system consists of two units, a
detector/amplifier and an attenuator. The detector/amplifier unit is inserted in the RF path on
the output of the power amplifier, and the attenuator is situated in the RF path between the
1st and 2nd stages of amplification.
Normally the attenuator is at minimum attenuation. The detector/amplifier unit monitors the
RF level being delivered by the power amplifier, and when a certain threshold is reached it
begins to increase the value of the attenuator to limit the RF output to the (factory set)
threshold. Therefore overloading of the power amplifier is avoided.
The factory set threshold is 1dB below the Enhancer 1dB compression point. Some
adjustment of this AGC threshold level is possible, a 10dB range is mostly achieved. It is
not recommended under any circumstances to adjust the AGC threshold to a level greater
than the 1dB compression point as system degradation will occur.
The detector comprises of a 50 transmission line with a resistive tap which samples a
small portion of the mainline power. The sampled signal is amplified and fed to a
conventional half wave diode rectifier, the output of which is a DC voltage proportional to
the RF input signal.
This DC voltage is passed via an inverting DC amplifier with integrating characteristics, to
the output, which drives the attenuation control line of the corresponding AGC attenuator.
This unit is fitted at some earlier point in the RF circuit.
The unit contains a 12V DC regulator in the detector module, which supplies stabilised
voltage to the DC amplifier and via an external cableform to the AGC attenuator.
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For small signals, below AGC onset, the output control line will be close to 12V and the
AGC attenuator will have minimum attenuation. As the signal level increases the control
line voltage will fall, increasing the attenuator value and keeping the system output level at a
constant value.
The AGC onset level is adjusted by the choice of sampler resistor R1 and by the setting of
potentiometer VR1.
The attenuator comprises a 50 P.I.N diode, voltage-variable attenuator with a range of 3 to
30dB. The attenuation is controlled by a DC voltage which is derived from the associated
AGC detector unit.
5.2.9.2 Technical Specification
PARAMETER SPECIFICATION
Frequency Range: up to 1000MHz
Attenuation Range: 3 to 30dB
Attenuation Steps: continuously variable
VSWR: better than 1.2:1
RF Connectors: SMA female
attenuator: 1W Power Handling:
detector/amp: >30W (or as required)
operation: -10°C to +55°C Temperature
Range:
storage: -40°C to +70°C
attenuator (pcb) 50 x 42 x 21mm Size:
Detector (pcb) 54 x 42 x 21mm
attenuator: 90grams Weight:
detector/amp: 100grams
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5.2.9.3 Drg. N. 17-001105, ACG Detector Assembly
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5.2.9.4 Drg. N. 17-001175, Wide Range AGC Detector Circuit Diagram
The General Purpose Relay Board allows the inversion of signals and the isolation of
circuits. It is equipped with a single dual pole change-over relay RL1, with completely
isolated wiring, accessed via a 15 way in-line connector.
The relay is provided with polarity protection diodes and diodes for suppressing the
transients caused by "flywheel effect" which can destroy switching transistors or induce
spikes on neighbouring circuits. It’s common use is to amalgamate all the alarm signals
into one, volts-free relay contact pair for the main alarm system.
Note that the board is available for different voltages (12 or 24V) depending on the type
of relay fitted at RL1.
5.2.11 24V Flat-Pack PSU (96-300002)
5.2.11.1 Description
The power supply unit is a switched-mode type capable of supplying 24V DC at
6.25Amps continuously. Equipment of this type typically requires approximately 4.0-5.0
Amps at 24V DC, so the PSU will be used conservatively ensuring a long operational
lifetime.
No routine maintenance of the PSU is required. If a fault is suspected, then the output
voltage from the power supply may be measured on its output terminals. This is typically
set to 24.5V.
All the PSU’s used in AFL Cell Enhancers are capable of operation from either 110 or
220V nominal AC supplies. The line voltage is sensed automatically, so no adjustment or
link setting is needed by the operator.
5.2.11.2 Technical Specification
AC Input Supply:
110 or 220V nominal
Voltage:
90 to 132 or 180 to 264V
(absolute limits)
Frequency: 47 to 63Hz
DC Output Supply:
Voltage: 24V DC (nominal)
22 to 26V (absolute limits)
Current: 6.25A
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6. INSTALLATION
Initial Installation Record
6.1
When this equipment is initially commissioned, please use the equipment set-up record sheet
in Appendix A. This will help both the installation personnel and AFL should these figures
be needed for future reference or diagnosis.
General
6.2
The size and weight of the wall units mean that they represent a significant health hazard
unless they are mechanically installed in the correct manner. In the interests of safety this
should be done before any electrical, RF, or optical connections are made.
It is important in determining the location of the wall units that space is allowed for access
to the front and underneath of the equipment. To enable maintenance to be carried out, the
door must be able to fully open. The location must be served with a duct to allow the entry
of cables into the unit.
Electrical Connections
6.3
The mains power supply and the alarms are connected through an IP65 connector which
should need no further attention once connected. It is recommended that the AC power
connection is approved by a qualified electrician, who must satisfy himself that the supply
will be the correct voltage and of sufficient capacity.
All electrical and RF connection should be completed and checked prior to power being
applied for the first time.
Optical Connections
6.4
The optical input and output ports are be located on a bracket fixed to the lower inside of the
case. The optical fibres from the tunnels enter through a cable gland on the case underside
The ports are supplied with a green plastic cover, which must be removed prior to the
connection of the fibre cable. Ensure that transmitter and receiver fibre cable are identified
to prevent misconnection. At the master site, the fibre transmitters are in the downlink path
with the receivers in the uplink. At the remote sites the fibre transmitters are in the uplink
with the receivers in the downlink. Where some of the fibre optic transmitter outputs are
split with optical couplers to provide a connection to more than one remote site, care must be
taken to ensure that the correct connections are made.
Ensure that connections are kept clean and are fully tightened.
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RF Connections
6.5
All RF connections are made to the cable termination, located on the right-hand side of the
wall enclosure. Care must be taken to ensure that the correct connections are made with
particular attention made to the base station TX/RX ports. In the event that the base
transmitter is connected to the RX output of the rack, damage to the equipment may be done
if the base station transmitter is then keyed. If the environment where the equipment is
installed is deemed to be ‘wet’ i.e. water seepage through roofs or walls, then suitable
methods to seal the RF N type connectors should be used, for example self amalgamating
sealant tape.
Ensure that connections are kept clean and are fully tightened.
Commissioning
6.6
Once all connections are made the equipment is ready for commissioning.
To commission the system the test equipment detailed in section 7.2 will be required.
Using the system diagrams and the end-to-end test specification, the equipment should be
tested to ensure correct operation. Typical RF levels that are not listed in the end-to-end
specification, such as input levels to the fibre transmitters are detailed in the whole system
diagram in section 4.
On initial power up the system alarm indicators on the door of the equipment should be
checked. A red LED illuminated indicates a fault and that particular module must be
investigated before proceeding with the commissioning. A green LED illuminates, to
indicate that the power supply is connected and valid.
The individual fibre optic units are fitted with a pair of status indicators on their front
panels. One is a green LED, which indicates that the unit is connected to a 15 Volt power
supply. This indicator is common to both transmit and receive units. The second LED on the
transmitter indicates that the laser is operating. On the receive unit the second LED indicates
that a light signal is being received.
When all the fibre connections are completed and power to each site is connected each fibre
unit should show two illuminated indicators.
In the event that any part of the system does not function correctly as expected, check all
connections to ensure that they are to the correct port, that the interconnecting cables are not
faulty and that they are tightened. The majority of commissioning difficulties arise from
problems with the interconnecting cables and connectors.
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7. MAINTENANCE
General Procedures
7.1
7.1.1 Fault Finding
In the event that the performance of the system is suspect, a methodical and logical approach
to the problem will reveal the cause of the difficulty. The System consists of modules within
a wall mounted, environmentally protected enclosure.
Transmissions from the main base stations are passed though the system to the mobile radio
equipment; this could be a handheld walkie-talkie, mobile telephone or a transceiver in a
vehicle. This path is referred to as the downlink. The return signal path from the mobile
radio equipment to the base station is referred to as the uplink.
The first operation is to check the (optional) alarms of each of the active units and determine
that the power supplies to the equipment are connected and active.
This can be achieved remotely (via CEMS, the digital RS232 C
ystem, if fitted), or locally with the front door LED’s. The green LED on the front door
S
ell Enhancer Management
should be illuminated, while the red alarm indicator should be off.
If an Alarm is on, then that individual module must be removed and tested against the
original test specification.
The individual amplifier units have a green LED showing through a hole in their piggy-back
alarm board (or directly through a hole in the amplifier lid), which is illuminated if the unit
is working correctly.
If an amplifier is suspect, check the DC power supply to the unit. If no other fault is
apparent use a spectrum analyser to measure the incoming signal level at the input and then
after reconnecting the amplifier input, measure the output level. Consult with the system
diagram and amplifier specification to determine the expected gain and compare result.
In the event that there are no alarms on and all units appear to be functioning it will be
necessary to test the system in a logical manner to confirm correct operation.
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7.1.2 Downlink
Confirm that there is a signal at the expected frequency and strength from the base station. If
this is not present then the fault may lay outside the system. To confirm this, inject a
downlink frequency signal from a known source at the master site BTS input and check for
output at the remote site feeder output.
If a signal is not received at the output it will be necessary to follow the downlink path
through the system to find a point at which the signal is lost. The expected downlink output
for the given input can be found in the end-to-end test specification.
7.1.3 Uplink
Testing the uplink involves a similar procedure to the downlink except that the frequencies
used are those transmitted by the mobile equipment.
7.1.4 Fault repair
Once a faulty component has been identified, a decision must be made on the appropriate
course to carry out a repair. A competent engineer can quickly remedy typical faults such as
faulty connections or cables. The exceptions to this are cable assemblies connecting
bandpass filter assemblies that are manufactured to critical lengths to maintain a 50-ohm
system. Care should be taken when replacing cables or connectors to ensure that items are of
the correct specification. The repair of component modules such as amplifiers, tuned cavities
or bandpass filters will not usually be possible in the field, as they frequently require
specialist knowledge and test equipment to ensure correct operation. It is recommended that
items of this type are replaced with a spare unit and the faulty unit returned to AFL for
repair. If spare parts need to be ordered from AFL, be sure to quote the serial number of the
Cell Enhancer/Repeater and the serial number [and frequencies] of the module(s) to be
replaced.
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7.1.5 Checking service
Following the repair of any part of the system it is recommended that a full end-to-end test is
carried out in accordance with the test specification and that the coverage is checked by
survey.
It is important to bear in mind that the system includes a radiating cable network and base
stations that may be faulty or may have been damaged.
7.1.6 Service Support
Advice and assistance with maintaining and servicing this system are available by contacting
Aerial Facilities Ltd.
Tools & Test Equipment
7.2
The minimum tools and test equipment needed to successfully service this AFL product are
as follows:-
Spectrum analyser: 100kHz to 2GHz (Dynamic range = 90dB).
Signal Generator: 30MHz to 2GHz (-120dBm to 0dBm o/p level).
Attenuator: 20dB, 10W, DC-2GHz, (N male – N female).
Test Antenna: Yagi or dipole for operating frequency.
Optical Power Meter: 1300 – 1560nM (-40 - +10dB)
Digital multi-meter: Universal Volt-Ohm-Amp meter.
Test cable x 2: N male – N male, 2M long RG214.
Test cable x 2: SMA male – N male, 1m long RG223.
Hand tools: Philips #1&2 tip screwdriver.
3mm flat bladed screwdriver.
SMA spanner and torque setter.
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Care of Modules
7.3
7.3.1 General Comments
Many of the active modules contain semiconductor devices utilising MOS technology, which
can be damaged by electrostatic discharge. Correct handling of such modules is mandatory to
ensure their long-term reliability.
To prevent damage to a module, it must be withdrawn/inserted with care. The module may
have connectors on its underside, which might not be visible to the service operative.
7.3.2 Module Removal (LNA’s, general procedure):
The following general rules should be followed to remove a module:
1 Remove power to the unit
2 Remove all visible connectors (RF, DC & alarm)
3 Release module retaining screws.
4 Slowly but firmly, pull the module straight out of its position. Take care not to twist/turn
the module during withdrawal. (When the module is loose, care may be needed, as there
may be concealed connections underneath).
7.3.3 Module Replacement (general):
1 Carefully align the module into its location then slowly push the module directly straight
into its position, taking care not to twist/turn it during insertion.
2 Reconnect all connectors, RF, alarm, power etc.,(concealed connectors may have to be
connected first).
3 Replace retaining screws (if any).
4 Double-check all connections before applying power.
7.3.4 Power Amplifiers
1) Remove power to the unit. (Switch off @ mains/battery, or remove DC in connector)
2) Remove alarm wires from alarm screw terminal block or disconnect multi-way alarm
connector.
3) Carefully disconnect the RF input and output coaxial connectors (usually SMA)
If alarm board removal is not required, go to step 5.
4) There is (usually) a plate attached to the alarm board which fixes it to the amplifier,
remove its retaining screws and the alarm board can be withdrawn from the amplifier in
its entirety. On certain types of amplifier the alarm board is not
mounted on a dedicated
mounting plate; in this case it will have to firstly be removed by unscrewing it from the
mounting pillars, in most cases, the pillars will not have not have to be removed before
lifting the amplifier.
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5) If the amplifier to be removed has a heatsink attached, there may be several different
ways it can have been assembled. The most commonly used method, is screws through
the front of the heatsink to threaded screw holes (or nuts and bolts), into the amplifier
within the main case. If the heatsink is mounted on the rear of the main case (e.g., against
a wall in the case of wall mounted enclosures), then the fixing method for the heatsink
will be from within the case, (otherwise the enclosure would have to be removed from the
wall in order to remove the heatsink).
When the heatsink has been removed, the amplifier may be unscrewed from the main
casing by its four corner fixings and gently withdrawn.
Fitting a new power amplifier module will be the exact reverse of the above.
Note: Do not forget to apply fresh heatsink compound to the heatsink/main case
joint and also between the amplifier and the main case.
7.3.5 Low Power Amplifier Replacement
1 Disconnect the mains power supply and disconnect the 24V dc supply connector for the
LPA.
2 Disconnect the RF input and output cables from the LPA.
3 Disconnect the alarm connector.
4 Remove the alarm monitoring wires from (D type connector) pins 9 and 10.
5 Remove the LPA module by removing the four retaining screws, replace with a new
LPA module and secure it with the screws.
6 Connect the RF cables to the LPA input and output connectors. Reconnect the wires to
the alarm board connector pins 9 and 10.
7 Reconnect the DC supply connector and turn the mains switch on.
Note: Tighten SMA connectors using only a dedicated SMA torque spanner. If
SMA connectors are over-tightened, irreparable damage will occur. . Do not use
adjustable pliers to loosen/tighten SMA connectors.
Also take care not to drop or knock the module as this can damage (or misalign in the
case of tuned passive modules) sensitive internal components. Always store the modules
in an environmentally friendly location
7.3.6 Module Transportation:
To maintain the operation, performance and reliability of any module it must be stored and
transported correctly. Any module not installed in a whole system must be kept in an antistatic bag or container. These bags or containers are normally identified by being pink or
black, and are often marked with an ESD label. Any module sent back to AFL for
investigation/repair must be so protected. Please contact AFL’s quality department before
returning a module.
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Maintenance Handbook
Date:-04/01/2006
Page:-
62 of 63
APPENDIX A INITIAL EQUIPMENT SET-UP CALCULATIONS
GENERAL INFORMATION
Site Name: Client Name:
Date: AFL Equip. Model N.
ANTENNA SYSTEMS
A - Service Antenna
B – Donor Antenna
C – Service Feeder
D – Donor Feeder
G – Input signal level from donor BTS
Parameter Comments Value
Input signal level (G)
CE max. o/p power (E)
Service antenna gain (A)
Service antenna feeder loss (C)
Effective radiated power (ERP)
Model Gain Azimuth Comments
Type Loss Length Comments
INITIAL PARAMETERS
E – CE Output Power
F – Antenna Isolation
Operating Voltage V
DOWNLINK CALCULATIONS
dBm
dBm
Gain setting
Isolation required(Gain + 10dB) dB
Attenuator settingCE gain-gain setting dB
E - G
dB
dB
E+A-C
dBm
dB
dBm
dBm
If the input signal level in the uplink path is known and steady, use the following calculation
table to determine the gain setting. If the CE features Automatic Gain Control the attenuator
should be set to zero and if not, then the attenuation setting for both uplink and downlink
should be similar.
UPLINK CALCULATIONS
Parameter Comments Value
Input signal leveldBm
CE max. o/p power (E)
Gain settingdB
Required isolationdB
Donor antenna gain (B)
Donor antenna feeder loss (D)
Effective radiated power (ERP)
Attenuator setting(CE gain-gain setting) dB
dBm
dB
dB
E+B-D
dBm
dB
H/book Number:-60-056100HBKMFCC
Issue No:-2
P B L Tunnel Units 1 & 2
Maintenance Handbook
Date:-04/01/2006
Page:-
63 of 63
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